Among the important and time consuming tasks in surgical procedures is the anastomosis or joining of severed blood vessels, and the success of a surgical procedure may depend on the degree of circulation which is restored through such anastomosis. Anastomosing of blood vessels is a tedious procedure, particularly in blood vessels of small diameter including blood vessels less than one mm. in diameter. Conventional blood vessel suturing techniques are time consuming, extending the duration of a surgical procedure and successful anastomosing of blood vessels is highly dependent on the proper placement of sutures by the surgeon. Similar difficulty is often encountered in anastomosing synthetic tubular graft materials to existing vessels of the body.
Various methods and devices for performing an end-to-side anastomosis are known within the art of surgery. Most of these known methods are, however, time-consuming, and thus not suitable for use when time is at a premium and a quiet field of operation is needed, as for example in the case of coronary bypass operations.
U.S. Pat. No. 4,624,255 discloses an anastomosis device wherein a member, preferably in the form of a ring, has structure for tethering the blood vessel portions thereto under radial stress with the intima of the blood vessel portions opposed. During surgery, the ring is disposed around an end of one of the severed blood vessel portions, and the blood vessel portions are tethered to the ring at least three spaced apart locations stressing the blood vessel portions radially outward in several directions to evert the intima and hold the intima of the two portions against each other. To hold blood vessel portions in close proximity during anastomosis, a pneumatic clamping device is provided which grips the blood vessel portions with a force according to the fluid pressure supplied thereto.
U.S. Pat. No. 4,523,592 discloses an anastomotic coupling device wherein a pair of coupling disc members cooperate to couple two vessels, one of the members having spaced apart hook members, and the other member having receptor cavities aligned with said hook members for locking the members together in a successful anastomatic procedure with tissue everted and secure on said hook members.
U.S. Pat. No. 4,366,819 discloses an anastomotic fitting for coronary artery bypass graft surgery having an assembly of four components including a cylindrical tube having at least one ring flange locking indentation in an inflow end and a plurality of locking ring grooves in an outflow end, a ring flange having a central aperture and pluralities of long and short spikes, the long spikes engaging in the locking indentation, with a graft engaged therebetween, a fixation ring having a central aperture and a plurality of spikes positioned about the aperture, and a locking ring having an aperture with a plurality of locking ring ridges for engagement with the locking ring grooves. At surgical implantation an aortic wall having a hole therein engages between the ring flange and the fixation ring and is held in position by the spikes of the fixation ring, and the four components engage together forming an integral anastomotic fitting.
U.S. Pat. No. 5,366,462 discloses a method of using a staple for joining first and second blood vessels wherein a staple having an open center is provided to staple the two vessels together. One end of the first blood vessel is placed through the staple and then pierced by an end of the staple. An opening in the side of the second blood vessel is formed and the pierced end of the first blood vessel is inserted into the hole. A second end of the staple is then deflectively bent and pierces the outer wall of the second vessel to staple the two vessels together.
U.S. Pat. No. 4,917,087 discloses devices, kits and methods for non-suture end-to-end and end-to-side anastomosis of tubular tissue members employing tubular connection members having clip retaining elements comprising annular groove or flanges in the connection members and spring clips which comprise a ring-shaped body with separable opposed ends whereby a circular opening defined by the body can be enlarged. The opposed ends have handling elements to facilitate handling of the clips and separation of the opposed ends.
It is a general object of the present invention to provide methods and apparatus which simplify surgical anastomosis techniques and which effect an anastomosis with substantial assurance of patency.